THE VERDICT on America’s 18-year-olds’ performance is that overall it is merely holding steady - despite a 40 per cent increase in spending on education over the past two decades.

At the same time, more high school graduates than ever are going on to college and record numbers of those who have dropped out are going back to complete the equivalent of high-school courses.

Some analysts argue that it is the bulge in the number of college-bound students that is holding down the measures of their overall performance. Record numbers are taking the two principal tests used for college admission: the Scholastic Assessment Test (SAT) and American College Testing examination (ACT).

A record 995,000 students - almost 60 per cent of those entering college - took the ACT last year, an increase of nearly 200,000 since the beginning of the decade. ACT officials say more colleges are accepting the scores in their exam as an alternative to the SAT and many students prefer it because it tests achievement rather than aptitude. Despite the increase , the average score remained flat at 21 out of a possible 36.

The SAT is divided into two sections and it is taken annually by more than 1.1 million students. Average SAT scores for mathematics inched up to 511 out of a possible 800, the highest level in 26 years, while the verbal score remained flat at 505, also out of 800.

Officials of the College Board, which administers the test, say a declining number of students who take English courses in high school was to blame for the stagnant verbal score.

There is also evidence that 18-year-olds are enjoying higher school grades than they deserve. The proportion of SAT test-takers with an A average, the highest grade, has increased to 37 from 28 per cent in the past 10 years, while their SAT scores have fallen a combined average of 14 points.

It was also announced earlier this year that American students about to graduate from high school had scored near the bottom on the Third International Maths and Science Study, placed 19th out of 21 developed nations in maths and 16th out of 21 in science.